#include<stdio.h>
int main()
{

	char ch1 = 'A', ch2 = 'B', c;
	printf("ch1=%c\nch2=%c\n", ch1, ch2);
	c = ch1;
	ch1 = ch2;
	ch2 = c;
	printf("ch1=%c\nch2=%c\n", ch1, ch2);
	return 0;
}